1. Field of the Invention
The invention relates to a water jet aerator for sanitary fittings and the like with at least one device for producing individual jets, at least one chamber positioned below it for the air supply and at least one device for splitting up and mixing the individual jets with air.
2. Prior Art
Aerators for sanitary fittings are widely used nowadays, because an aerated or ventilated water jet does not splash and permits a quiet flow of water. For many uses, such as washing the hands, the quantity of water can be reduced without to any disadvantage effects in the ventilated jet.
Known devices for producing the individual jets are constructed in a substantially standardized manner. One or more superimposed perforated plates are provided successively in the direction of flow, the holes normally being displaced transversely relative to one another. Below the last perforated plate there is usually a free space, with passages for air supply from the outside, so that air can be sucked into the free space.
In known jet aerators or ventilators, there are considerable differences in the way in which the individual jets are split up. Thus, in many conventional jet aerators, there is a screen or sieve arrangement of several superimposed screens or sieves, which split up the jet and bring about the mixing with air. However, such jet ventilators have a tendency to clog through liming. German Auslegesschrift No. 2,114,618 discloses a jet ventilator, in which the individual jets strike against the sloping surfaces of a mushroom-type baffle plate and are thereby split up and mixed with the air. However, the mushroom-shaped member takes up a considerable portion of the passage cross-section, so that there is a considerable flow restriction and an unfavorable cross-sectional ratio. This is even more apparent in the case of the jet ventilator according to German Offenlegungsschrift No. 2,821,195, in which the individual jets are directed against baffle plates, which reflect the jets backwards against the flow. European Patent application No. 82102033, which corresponds to U.S. Pat. No. 4,474,329--Finkbeiner, discloses a shower head which makes it possible to form a plurality of individual ventilated shower jets. For this purpose, passages with relatively small axial obstruction are provided, inner walls of the passages having obstacles for separating and splitting up the individual jets. The ventilated jets passing out of these passages have a relatively small cross-section. They are suitable for a shower head, but are less suitable for the outlet of a mixing valve, a bath outlet or the like.